ABSTRACT
BACKGROUND: To investigate the thalamic neurotransmitters and functional connections in the development of chronic constriction injury (CCI)-induced neuropathic pain. METHODS: The paw withdrawal threshold was measured by mechanical stimulation the right hind paw with the von frey hair in the rats of CCI-induced neuropathic pain. The N-acetylaspartate (NAA) and Glutamate (Glu) in thalamus were detected by magnetic resonance spectrum (MRS) process. The thalamic functional connectivity with other brain regions was scanned by functional magnetic resonance image (fMRI). RESULTS: The paw withdrawal threshold of the ipsilateral side showed a noticeable decline during the pathological process. Increased concentrations of Glu and decreased levels of NAA in the thalamus were significantly correlated with mechanical allodynia in the neuropathic pain states. The thalamic regional homogeneity (ReHo) decreased during the process of neuropathic pain. The functional connectivity among the thalamus with the insula and somatosensory cortex were significantly increased at different time points (7, 14, 21 days) after CCI surgery. CONCLUSION: Our study suggests that dynamic changes in thalamic NAA and Glu levels contribute to the thalamic functional connection hyper-excitation during CCI-induced neuropathic pain. Enhanced thalamus-insula functional connection might have a significant effect on the occurrence of neuropathic pain.
Subject(s)
Animals , Rats , Thalamus/metabolism , Wounds and Injuries/physiopathology , Neurotransmitter Agents/metabolism , Neuralgia , Thalamus/physiopathology , Aspartic Acid/analogs & derivatives , Aspartic Acid/metabolism , Glutamic Acid/metabolism , Constriction , HyperalgesiaABSTRACT
OBJECTIVE: To explore the precise mechanism of electroacupuncture (EA) to delay cognitive impairment in Alzheimer disease. Methods N -Acetylaspartate (NAA), glutamate (Glu) and myoinositol (mI) metabolism were measured by magnetic resonance spectroscopy, learning and memory of APP/PS1 mouse was evaluated by the Morris water maze test and the step-down avoidance test, neuron survival number and neuronal structure in the hippocampus were observed by Nissl staining, and BDNF and phosphorylated TrkB detected by Western blot. RESULTS: EA at DU20 acupuncture significantly improve learning and memory in behavioral tests, up-regulate NAA, Glu and mI metabolism, increase the surviving neurons in hippocampus, and promote the expression of BDNF and TrkB in the APP/PS1 transgenic mice. CONCLUSION: These findings suggested that EA is a potential therapeutic for ameliorate cognitive dysfunction, and it might be due to EA could improve NAA and Glu metabolism by upregulation of BDNF in APP/PS1 mice.
Subject(s)
Animals , Male , Mice , Electroacupuncture/methods , Aspartic Acid/analogs & derivatives , Glutamic Acid/metabolism , Hippocampus/chemistry , Learning/physiology , Memory/physiology , Protein-Tyrosine Kinases/analysis , Magnetic Resonance Imaging , Membrane Glycoproteins/analysis , Mice, Transgenic , Magnetic Resonance Spectroscopy , Random Allocation , Blotting, Western , Aspartic Acid/metabolism , Maze Learning , Brain-Derived Neurotrophic Factor , Models, Animal , Exercise Test , Hippocampus/diagnostic imaging , Inositol/analysisABSTRACT
0.05). Conclusions: There exists an abnormal reduction of neural viability and function on bilateral hippocampus of patients with first-episode MDD.